 In
cooler parts of the planet, away from the Equator line, clouds
can stretch up into air which is below freezing. These clouds
are a mixture of water droplets, lower down, and ice crystals
and special supercooled water droplets higher up. At the bottom
of the cloud, millions of tiny water droplets collide to form
big droplets, which collide forming bigger ones. This process
is called coalescence. Another process called accretion happens
higher up. The ice crystals attract the supercooled droplets,
which freeze onto them. As the crystals grow and stick to others,
they form snowflakes which fall as snow when heavy and if the
temperature on the ground is freezing. |
Click below if you have clicked on Winter Tour on the Winter
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